The basic idea is to have a playback script that does just a single page.

Then, using the "detailed timings" option, and after running the script, you can have eValid generate a chart that shows the individual components of the page and how long each one took to download.

This is most useful if you are trying -- as many performance enhancement projects try to do -- to find the slowest components in a page so you can speed them up (by making them smaller, or breaking them into parts).